The following schedule is tentative and subject to change without notice.

Credit: Most of slides for this lecture are based on materials provided by the authors of the textbook and references.

For project submission and automatic grading, we are running a dedicated server at https://sys.snu.ac.kr. If you want to access the sys server outside of the SNU campus, please send a request via a Google Form whose URL is posted in the eTL.

Project #5: Native Thread Support

The current version of the xv6 kernel is designed to support old-fashioned processes only. This project involves extending the xv6 kernel to incorporate native thread support. The primary goal is to enable user processes to create and manage user-level threads. Our threading system adheres to the 1:1 threading model. This means that for each user-level thread created, a corresponding kernel thread should be created within the kernel. You must ensure the integration of this new feature does not disrupt the existing process management functionalities of the xv6 kernel.

• Project specification available here
• Due date: 11:59PM, December 22 (Friday).

Project #4: mmap() with Huge Pages

In this project, we implement a simplified version of the mmap() system call using 2MiB huge pages supported by the RISC-V architecture. The goal of this project is to understand the paging hardware of the RISC-V processor and how the operating system manages virtual-to-physical address mapping to improve memory efficiency.

• Project specification available here
• Due date: 11:59PM, November 25 (Saturday).

Project #3: BTS (Brain Teased Scheduler)

Currently, the CPU scheduler of xv6 uses a simple round-robin policy. The goal of this project is to understand the scheduling subsystem of xv6 by implementing the scheduler named BTS (Brain Teased Scheduler).

• Project specification available here
• Due date: 11:59PM, October 31 (Tuesday).

Project #2: System calls

System calls are the interfaces that allow user applications to request various services from the operating system kernel. This project aims to understand how those system calls are implemented in xv6.

• Project specification available here
• Due date: 11:59PM, October 8 (Sunday).

Project #1: Hello world, xv6

xv6 is an instructional operating system developed by MIT based on Ken Thompson and Dennis Ritchie’s Unix version 6 (v6). In this course, we will use xv6-riscv, the version recently ported to a multi-core RISC-V machine. The goal of this project is to make your Linux or macOS development environment ready and get familiar with our project submission server.

• Project specification available here
• Due date: 11:59PM, September 18 (Monday).

xv6 Resources

• xv6 source code: https://github.com/snu-csl/xv6-riscv-snu (our customized version)
• xv6: a simple, Unix-like teaching operating system
• The RISC-V Reader: An Open Architecture Atlas
• RISC-V: An Overview of the Instruction Set Architecture
• RISC-V Instruction Set Manual Volume I: Unprivileged ISA, Version 20191213
• RISC-V Instruction Set Manual Volume II: Privileged Architecture, Version 20211203